Electrically-heated soldering-iron



My 2, 1933. F. DUPAU 1,906Q225 y ELECTRICALLY HEATED SOLDERING IRON I Filed April 14, 1932 2 Sheets-'Sheet 1 ATTORNEY May 2, 1933. F. nUPAu ELEGTRICALLY HEATED SOLDEHING I'RO'NJ 2 Sheets-Sheet 2 Filed April 14.a 1932 'ffr/w No 00ml/ I Arran/ver.

Patented 1933` UNITED STATES' PATENT y OFFICE,

IEBN'AND DUPAU, OF'PABIS, FRANCE i ELECTBCALLY-B'EATED BLDERING-IRON applicati@ mea April u, 1932, serial No. 605,316, and m France apniis, 19m.

The present invention relates to solderingirons of the electrically-heated type, its primary object being to provide an 1m roved l solderin -iron of this type utilizing so der in wire, strlp or cord form, by Imeans of which theoperator can, single-handed,y apply solder with the desired accuracy to any piece of work for any len h 'of time while having the possibility of strictly regulating the feed of the solder inv proportion as it is needed, merely by exerting in a most easy way a small stress with one finger of his hand hold'- ing the iron, which' obviates any waste or un'- due scattering of the molten solder while leavin the other hand 'of the operator entirely ree.

'A further object of the invention is to provide an electrically-heated solderingiron of simple, rugged and yet light construction which the operator can manipulate single-handed -without becoming unduly tired and -without getting his hand holding'the iron handle scorched even by prolonged contact with said handle.

Astill further object of the invention is to provide an electrically-heated solderingiron wherein the heat generated by one or more electrical heaters is used with the utmost efficiency for melting-the solder in proportion as the latterin wire or cord form enters a recess formed in a block carrying lsaid heaters and formed with the bit, the quantity of heat, i.'e. of electric current necessitated to properly operate the solderingiron, being strictly limited to the required quantity of solder to be appliedfto the work piece, this limitation being at all times under the easy control of the.- operator who can i vperform the whole soldering operation single-handed. y

Still a further object of the invention is to provide an electrically-heated solderingiron wherein the solder in wire orcord form,

5 supplied for example from a spool or .reel

carried by the handle of the tool, is sothermallysheathedy till it is molten as to be protected from premature fusion, which obw viates the risk of any breakdown or undue stoppage of the working of the tool due to clogging evenafter a lengthy soldering operation.. f VWith these and such other objects in view aswill incidentally a pear hereinafter, the

invention is exempli ed by the novel construction and arrangement of parts that will now be described with reference to the accompanying drawings forming a part of the present disclosure and wherein:

Figure 1 is a longitudinal sectional view 50 of a soldering-iron constituting a first embodiment of the invention.

Figure 2 is a plan view, partly in section on the line II-II of Fig. 1'.

Figure 3 is a transverse sectional view on 65 the line III-III of Fig. 1.

Figure 4 is a longitudinal sectional view on the line IV-IV ,of Fig. 5 of a solderinglron constituting a further embodiment of the invention.. i

Figure 5 is a plan view corresponding to Fig. 4 and showing the oblique arrangement of the solder .wire actuating or driving roller.

Figure 6 is a transverse sectional view on 75 the line'VI-VI of Fig. 5.

- Like referencel numerals designate vlike part-s throughout the several views.

As illustrated in Figures 1 to 3, the soldering-iron comprises a handle 1 of round cross- 30 section, made for example of ebonite and formed along its longitudinal axis with a bore 2 in4 which fits a projecting tube 3 sheathed internally with a tubular lining 4 made of asbestos, mica or other suitable insulating substance.

At the fore end of the tube 3 is screwed a metal block 5 adapted to form the heating mass of the iron and to melt the solder. This block 5 is tapered at one end 5 to -form the 90 bit of the soldering-iron and is hollowed to y 4form an inner recess or fusion chamber 6 which is stopped at oneend by a screwthreaded plug 5b and extends at its opposite l end in the form of a duct 7 of small crosssectional area, the mouth of which is located substantially midway of the width of the bit 5". The bore 2 of the handle 1 communiber 6.

The heating of the block 5 is performed by two electrical resistances' 8 clamped against its side faces by cheek plates 9 secured to said faces by screws 8a.

The electrical resistances 8 are fed in parallel by leads 10, 10* clamped to terminals 11, 11 (Fig. 2) carried internally by the handle 1. These terminals are connected to conductors 12, 12a extending through bores 13, 13 of the handle.

The bores 13, 13 terminate in a header 14 closed by a cap 14 secured by screws 14 to the fore end ofthe handle 1. In the header 14 each of the conductors 12, 12aL extends in the form of two parallel wires respectively sheathed in a pairof tubes 15, 16 located on both sides of the tube 3, and feeds one of the resistances 8.

The soldering-iron thus constructed utilizes solid solder in wire or cord form. The solder wire or cord 17 passes freely through the bore 2 right into the fusion chamber 6. In this chamber, the tip of the solder` wire or cord 17 is melted by radiation from the metal block 5 heated by the resistances 8. The molten solder flows automatically through the duct 7 formed in the bit 5 whence it can be spread or applied in spot, tack or line form upon the work piece to be soldered. rEhe cross-sectional area of the duct 7 is so reckoned as to ensure the distribution of the solder in good conditions.

The particular arrangement of the fusion chamber 6 in the mass of the heating block 5 ensures rapid melting of the solder and permits it to utilize the heat generated by the resistances 8 with the utmost efficiency.

The solder wire 17 is protected as it progresses through the bore 2 by the insulating lining 4 which sheathes it onto its ingress into the fusion chamber 6 and thereby prevents it from becoming prematurely fused in said bore and from choking it accidentally.

In proportion as the end or tip of the solder wire 17 melts away in the fusion chamber 6, said wire may be fed onwards through the bore 2 by means of a driving device pro- `vided for that purpose upon the handle 1.

This driving device comprises, on the one hand, a knurled roller 18 located in a slot 19 through which the bore 2 commu-nicates with the atmosphere and revolubly mounted on a stationary pin 20, and, on the other hand, opposite the roller 18 a second knurled roller or pressure roller 21 located in another slot 22 of the handle l.

The pressure roller 21 is fitted on the end of a lever 23 pivotally mounted on a stationary pin 24. y

The solder wire or cord 17 passes between the two knurled rollers 18, 21 and, owing to the provision of a blade spring 25 secured to the handle 1 and whose end abuts on the lever 23, the said wire or cord is in turn pressed against the roller 18 with a sutliclent pressure for permitting a rot-ation imparted y the operator to said roller in the direction shown by the arrow F to drive the solder wire or cord 17 through the bore 2 towards the block 5.

The roller 18 projects out of the slot 19 so that the operator can easil actuate it, for example with the thumb nger of his hand that holds the handle of the tool. The roller 18 is advantageously positioned adjacent the fore end of the handle 1 to permit easier handling.

According to the further embodiment of the invention shown in Figures 4 to 6, the plug 5b is dispensed with for permitting the fusion chamber 6 to freely communicate with the atmosphere, whereby the small quantity of fumes or vapors that may evolve from the molten solder can freely escape.

Moreover each of the cheek plates 9 enclosing and holding the electrical resistances 8 has a boss 9a co-operating with the boss of v the companion cheek platev 9 to permit a tight fit of the fore end of the tube 3.

The driving knurled roller 18 projects outside the handle 1 but at an acute angle (see Fig. 5) to that longitudinal axial plane of the tool that intersects the axis of the solder duct 7 at right angles. This arrangement facilitates the manipulation of the solderingiron since it permits a better and more normal action of the operators thumb inger on the roller 18 while he is holding the soldering-iron with the same hand, particularly when soldering slanting or undercut work pieces.

In the constructional form shown in Figures 4 to 6, the second roller 21 is dispensed with and the blade spring 25 is secured to the lining 4 and presses directly on the solder wire 17 opposite the point of tangency of the roller 18.`

The operation of the soldering-iron as shown in Figures 4 to 6 is substantially the same as the one of the embodiment described with reference to Figures l to 3, but the handlin is facilitated as above-stated due to the o lique location of the driving roller 18, while the fumes or vapors from the solder that is molten in the chamber 6 freely escape and thus do not risk interference with the proper flow of the molten solder through the duct 7 onto the work piece or to give rise to calamine ory dirt that might otherwise clo said duct.

umerous minor constructional details might of course be changed without departing from the spirit of the invention and the ambit of the subjoined claims.

What I claim is:

1. A soldering-iron comprising, in combination, a handle having an axial bore and a slot extending from its bore, a tube fitted in the bore of the Ahandle and projecting from one of its ends, a block secured to the free internal chamber communicating with4 thetube and extended by a narrow duct formed through the bit, an electrical heater mounted on the block, conductors leading to said heater, and a-friction` member mounted inthe handle slot 'and projecting out of the handle and into its axial bore for engaging a wire or cord of solder insertable through said bore and said tube.v

2. A soldering-iron comprising, in combination, a handle havingj an axial bore and a' short slot extending from its bore, a tube fitted in the bore of the handle and projectingy from one of its ends, a block secured to the free end of the tube at an angley thereto and' tapered to form a bit, said block having an internalchamber communicating with the tube and extended by a narrow duct formed through the bit, an electrical heater mountedvon'the block, conductors housed in the handle bore and tube and leading to said heater, and a friction member revolubly mounted in the handle slot and projecting out of the handle and into its axial bore for engaging a wire of solder insertable through said bore and said tube.

3". A soldering-iron comprising, in combination, a handle having an axial bore and a short ,slot extending from its bore, a tube fitted in the bore of the handle and projecting from its fore end, a block secured to the free end of the tube at right angles thereto and tapered to form a bit, said block having an inner chamber communicating with the tube and extended by a duct of small sectional area formed through the bit, an electrical heater mounted on the block, .conductors housed inthe handle bore and tubefand leadving to said heater, a friction member revolubly mounted in the handle slot and projecting out of the handle and into its axial bore,

' and a pressure member also projecting into said axial bore `for co-operating-with said revoluble friction member to engage between them a .wire ofsolder insertable through saidj so bore and said tube# t .j 4. A soldering-iron comprising, in combination, a handle having lan axialbore and a short slot adjacent its fore end and extend-l -ing .from its bore, a tube 4fitted in the bore of the' handle `and pro ecting 'from its fore end, an insulatin sheat linin the tube, a block secured t'o t Je freeend o the t'ube at right angles thereto and tapered to form a it said block having. an. inner chamber cornmunicating with the tube and extended by a -,duct of small .sectionaly area formed throu h the bit, electrical re'sistances mounted on t e block, conductors housed in the handle bore and tube and leading to said ,resistances, a friction member revolubly mounted in the handle slot and projecting out of the handle and into its axial bore, and a pressure meminto sai axial bore for S0-operating w1 member to engage-between-them a wire of` soer insertable through said bore and said tu 5. A solderingron comprising,- in combination', a handle of round crosssection made of insulating material.l having an axial bore and a short radial slot extending from its bore adjacent its fore` end, a tube fitted in the bore ofthe handle 'and projecting from its fore end, an insulating sheath internally lining the tube, anjj'nternally recessed block tapered to form a bit and secured tothe free end ofthe tube perpendicularlyv to its axis', said block being'set at an angle to the plane of the handle slot, lthe recess inthe block .communicating with the tube and being freely opened at one end to the atmosphere and extended at its opposite end by' a' duct of small sectional area formed throu h the bit, electrical ristances mounted on oth-sides of the block,conductors housed in the handle.

bore and tube and leadin to said resistances,

a friction roller mounte in the handle slot -and projecting out of the handle dnd into 'its axial bore, and a springy pressure member l also `projecting into said axial bore for cooperating with said roller to engage between nation, a handle of round cross-section made of insulating material having an axial bore and a short radial slot extending from its bore adjacent its fore end, a tube fitted in i the boreof the yhandle. and `projecting from its fore end, anyfinsulating sheath internally' lining the tube,.an internally recessed metal block tapered to form a bit and secured to the free end. of the tube perpendicularly to its axis, said block being Setz at'fan acute angle to the plane of the handle slot, the recess in the block communicating with'the` tube and being freely opened at one 'endA to theatmosphere and extended at its op osite end by a duct of small sectional area ormed through the bit, 4 electrical yresistances arranged. on f vboth sides of the block, cheek plates clamping said resistances tothe block, conductors l -housed in the handle bore andtube and ,leading to said resistances, a knurled lroller mounted inthe handle slot andfiprojectin out of the handle and .intoits axia bore, and

a spring pressure member also projecting said roller to engage between them and drive a wireof solder insertable through the bore and tube.

v In testimony whereofI aix m si ature.

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